Published European Patent Application No. 186,118 describes certain 2-(2'nitrobenzoyl)-1,3 cyclohexanedione compounds which have utility as herbicides. It indicates that, in preparing the desired benzoyl-1,3-cycloalkyldione end product, an enol ester precursor thereof is subjected to a rearrangement to the end product by use of a base in the presence of a "cyanide source" as catalyst. The types of cyanide sources enumerated are: alakali metal cyanides; cyanohydrins of methyl alkyl ketones; cyanohydrins of benzaldhyde or of C.sub.2 -C.sub.5 aliphatic aldehydes; tri (lower alkyl) silyl cyanides; and hydrogen cyanide itself which is said to be inexpensive and to produce a rapid reaction. This published patent application is devoid of any suggestion of using a trialkylsilylcyanohydrin as a catalyst for such an enol ester rearrangement reaction.
Trialkylsilylcyanohydrins are a known class of compounds. Certain trimethylsilylcyanohydrins have been characterized in Synthesis, March 1982, pp. 212-214 as being useful as acyl anion equivalents in many synthetic transformations and as reagents for the synthesis of alpha, beta-unsaturated nitriles, beta-amino-alcohols, delta.sup.2 -butenolides, and alpha-hydroxyamides. To the best knowledge of the present inventor, trialkylsilylcyanohydrin compounds have not been shown or been suggested as being useful as a catalyst for the conversion procedure of the instant invention or one similar to it.